Timing mechanism



H. E. SMITH TIMING HECHARISH March 12, 1929 Filed Aug 17, 1925 2 Sheets-Sheet l lFlq HAROLD ELNO SMITH IN v zu'row ATTOlK" E Y5 Pate rated Mar. 12, 192,9.

. 1,705,271 UNITED STATES PATENT OFFICE.

HAROLD ELNO SMITH, F CLEVELAND HEIGHTS, OHIO, ASSIGNOR TO THE APEX ELEG- TBICAL MANUFACTURING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

TIMING MECHANISM.

Application filed August. 17, 1923. Serial No. 657,88l3.

. This invention relates to time controlled mechanism and has for its object the provision of a simple and inexpensive device for the operation of a switch, valve, or other controlling means which can be operated either manually at any time or' automatically after the lapse of any predetermined period and in which the predetermined periodcan itself beenlarged, decreased, or terminated at any instant without waiting for the timing mechanism to run through its set course. Other objects relate to the provision of a mechanism wherein all the func- 'tions of operating the switch or valve (or other controlling means), adjusting the time interval, energizing the timing apparatus, and starting the chronometric train are performed by a single handle; to the provision of an electric time switch in which the 'chronometric devices are shielded from the magnetic influence of the electric current, while other objects and advantages will appear as the description proceeds. My improved device is primarily designed for use in connection with heating or lighting apparatus, as in cookstoves, either electric or gas, to turn 01f the heating agent after a predetermined interval depending upon the thing being cooked or to turn on the heating agent at a predetermined time; in electric sad, irons or other like articles to insure the current being turned off in sufiicient time to prevent fire in case the operator forgot to do so when finishing work; in window or street lighting to turn off the light after the desired number of hours; in house heating to start the furnace or hot water heater after a given period; in signaling to sound an alarm after any given length of time; and

in many other situation's.

In the drawings accompanying and forming a part of this application I have shown certain illustrative embodiments of my invention, although it will be understood that these constitute only a few of the physical forms in which my inventive ideacan be embodied and that all these and many more are intended to be covered by my claims.

Fig. 1 is a front elevationof a preferred embodiment of (my invention; Fig. 2 is a sectional view taken immediately inside the front plate thereof corresponding substantially to the line 22 of Fig. 3; Fig. 3 is a central vertical sectional view corresponding substantially to the line of Fig. 2;

Fig. 4 is a separated perspective view illustrating the arrangement and co-operation of the members of the winding arbor; Figs. 5 and 6 are views similar in general to Fig. 3 but illustrate modified arrangements of the mechanism; Fig. 7 is a detail view of the silent ratchet shown in Fig. 6; Fig. 8 is a sectional View corresponding to the line 88 in Fig. 2 and showing one of the arrangements of the magnetic shield; andFig. 9 illustrates a modified attachment of the operatin member to the arbor.

Descri ing by reference characters the parts shown in these drawings, 1 represents a casing having on its face a graduated dial 2 formed with a central. aperture 3, and mounted inside the casing is a frame 4 having journaled therein a spring arbor 5. Operatively connected to this arbor are a malnspring 6, a retarding gear 7, an operating member 8, a winding and setting handle9,

and a pointer 10, arranged and co-operating in various ways as will now be pointed out. In the embodiment shown in Figs. 1 to 4 inclusive, I have shown the spring as having its inner end secured to a'hub 12' which s I frictionally coupled to the arbor by means of a suitable friction gland, here comprising a washer 13 slidably splined to the arbor, a spring 14 and a tension nut 15, the outer end of the spring being connected to the frame in the usual manner (not shown). The opposite end of the hub 12 presses against some non-rotatable part carried by the arbor, in the present instance the ratchet 16, which in turn presses against an enlarged shoulder carried by the arbor.v Obviously this ratchet and shoulder could interchange places and other rearrangements could be made. Immediately adjacent the ratchet 16' is the wheel 7, the same being connected to the ratchet by the pawl 17. The wheel 7 is geared to a suitable retarding train, preferably a chronometer train, but not necessarily so inasmuch as a magnetic drag, a fly, a friction governor, anelectric motor or other retarding device could be employed within the scope of my invention.

Immediately outside the'frame 4 the arbor is squared for the rece tion of a second ratchet 20, and outside 0 this squared por-' tion tlie arbor is made cylindrical for the re- This member comprises a hub 21" outer end the prismatic boss 22 adapted for the reception of the corresponding socket carried by the handle 9; inside the casing this hub is provided with the operating member, 8 the particular design of which depends upon the nature of the apparatus or controlling device which is to be operated thereby, and also with the pawl 23 which cooperates with the ratchet 20. In the particular embodiment shown in Figs. 1 to '4 hereof the device to be operated consists of an electric switch having a fixed frame portion 25 carried by the inturned flange 26 of a back plate 27 with which the casing 1 is provided,

the switch also having a pivoted operated arm 28 adapted to oscillate between the positions shown in full and dotted lines in Fig. 2. In the particular arrangement herein shown the switch is closed when the parts occupy the full line position and open when they occupy the dotted line position, although it will be understood that I do not limit myself to this particular kind of switch or to this particular arrangement of switch or even to an; electrical device of any kind since the timing mechanism of my invention can equally well be employed in connection with a .valve or mechanical tiip or other type of mechanism. In this embodiment the arm 28 is provided at its end with a lateral pin 29 and the operating member 8 comprises an am having therein a slot 30 adapted to engage this pin and move the arm 28 in one direction or the otherf The end of the arm 8 is also provided with a finger 31 adapted when the arm 28is thrown in one direction to engage a suitable stop or shoulder 32 carried by some fixed part of the apparatus, such as the flange 26, and arrests the further movement of the same.

The parts are so arranged that the finger 31 engages the sto 32 at the same time that the pointer 10 indicates the zero of the dial.

' Upon turning the handle 9 and pointer 10 in a counter-clockwise direction, the arm 8 oscillates the lever 28 to full line position and simultaneously the pawl 23 engages theratchet 20 and thereby turnsthe arbor 5 in a direction to wind the spring 6, the ratchet 16 meanwhile turning freely ast the pawl 17. Upon releasing the hand e the engageinent of the ratchet 16 with the pawl 17 sets the retarding, train in operation, thereby returning the arbor gradually to its starting point; while the engagement of the ratchet 20 with the pawl 23 also returns the arm 8 to its starting point thereby throwing the lever 28 and bringing the. finger 31 back to the stop 32 at which oint the mechanism stops. However, shoul the operator change his or her mind and desire to forestall the action of the retardin train, the handle 9 can be set back manua ly at any time so as vto throw the lever 28, the pawl, 23 riding freely over the ratchet 20. In case this is done repeatedly it is clear that the spring 6 will be wound up more rapidly than it is permitted to run down, but overwinding of the same is prevented by the friction gland which enables the resetting of the mechanism even after the spring has been fully wound.

In the embodiment shown in Fig. 5 I have illustrated another form of my invention wherein the spring 6' has its outer end rigidly attached to a ring 35 which in turn is frictionally engaged by the collar 36 carried by the frame 4, thus preventing overwinding of the spring and enabling the parts to be reset even after the spring is fully .wheel 7 appears as before excepting that it has exchanged places with the ratchet 16. Outside of the frame 4 the arbor 5* is provided with a pinion 37 meshin with a gear 38 carried by a stud 39 an having the ratchet 2O rotatable therewith. The operating member 8 has its hub 21 projecting outside the casing and provided as before with handle 9 and pointer 10, this operating member also engaging the ratchet 2O through the agency of the pawl 23.

Obviously the gears 37 and 38 can be made with any desired ratio, either lengthening the time of operation or enhancing the accuracy of the mechanism. Owing to the reversal of the movement produced by gearing it will be noted that the setting will be accomplished by a clockwise movement or that the direction of the spring 6 and associated parts must be reversed. In this embodiment I have shown the operating member 8 as co-operating with the handle 28 of a valve 40 of conventional form.

Another modification is shown in Fig. 6 wherein the spring 6 is connected at its outer end to a stud 4 of the frame 4 and at its inner end to a hub 12 interposed between a fixed shoulder 42 carried by the arbor 5 and a friction gland also carried by the pawl 17. Thus far this arrangement is sub-' stantially like that in Fig. 3 excepting that the friction gland has been transferred to the opposite side of the spring.

In this embodiment, however, the end of the arbor 5" is equipped with a disk 44 carrying a ball clutch or silent awl indicated generally at 45 while 20' in lcates the disk or silent ratchet which is here made as a part of the operating member, the arm 8 and mechanism. The mode of operation of this device is, the same as that heretofore described excepting that the ratchet 20 being carried by the handle instead of by the arbor is necessarily reversed in position.

In Fig. 9 I have shown another mode of attaching the operating handle to the arbor which may be used with any of the spring mountings herein shown or even with a spring which is rigidly fastened at its two ends. 5 represents the arbor, 8 the operating member, 9 the handle and 10 the pointer as before. The handle and arm are connected rigidly together as by one of the same being pressed forcibly over the prismatic hub 21 of the other. This assembly is then frictionally coupled to the arbor in any suitable manner as by the clamping nut 46 screwed uponthe tapered split portion 47 of the hub 21. In use this friction is adjusted to such. a point that upon being turned forward it will wind the spring up to the desired limit of tension and then slip, and also to slip upon being manually set back.

In order to dispense with the necessity for using a non-magnetichair-spring, I preferably provide the mechanism with a magnetic shield when the same is employed in combination with an electric switch. To this end I interpose inthe frame 4 an iron plate48 suitably notched as shown at 49 for the accommodation of the frame members and also 'suitably slotted as shown at 50 to permit some member of the gear train to project therethrough. This plate can be either fiat or curved and can be located at any place, wherever most convenient to avoid conflict with the mechanism, provided only that it extend from one side of the casing 1 to the other, said casing being preferably made of cast iron which is both cheap and diamagnetic; The interior of this casing is preferably provided with an integral iron are enclosed in a magnetic shell, free from all variations in the field produced by the operation of the switch. v It will be understood that many other changes in detail can be made in addition to those herein pointed out, and that I do not limit myself in any wise except as specifically recited in my several claims or as necessitated by the prior art.

Having thus described my invention, what I claim is:

1. In time controlled mechanism the combination with a rotatable arnrand a handle for rotating the same in either direction, of a spring adapted to be wound by rotation of said arm in one direction, a ratchet device interposed betwecn the spring and arm to permit a manual rotation of said arm in the opposite direction, a retarding train for governing the unwinding of said spring, one end of said spring being frictionally secured whereby overwinding is prevented.

2. In a timing mechanism, the combination with a main spring of a winding arbor therefor, a handle, a ratchet device interposed between said handle and arbor to enable said handle to wind the spring wherb moved in one direction and to move freely in the other direction, a retarding train arranged to govern the unwinding movement of the spring, and an operating member movable with said handle in both directions, said spring being frictionally coupled to said arbor to prevent overwinding thereof.

3. In a timing mechanism, the combination with a main spring, of a winding arbor therefor, a handle for turning said arbor in a direction to wind said spring, a ratchet interposed between said handle and arbor to permit said handle toturn freely in the opposite direction, an operating member arranged to turn with said handle in both directions, and a retarding train operatively coupled to said arbor to govern the unwinding movement of the same, said arbor being frictionally coupled to said spring to permit the set-ting movement of said handle and member after the spring is fully wound.

4:. Timing mechanism, including a chronometric train, an arbor, two ratchets rigid therewith,one of said 'ratchets being operatively connected to. one member of the train, a winding handle operatively .connected to the other ratchet, an operating member rigid with said handle, and amain spring which is frictionally coupled to said arbor and adapted to drive said train.

In testimony whereof, I hereunto aflix my signature.

HAROLD ELNO SMITH. 

